A new Treasury report analysing the economic benefits of having a borderless United Kingdom, claims that the remaining part of a UK-wide single market would be worth £5 billion to Scotland over the next 30 years.

It argues that Scottish independence would create ‘significant headwinds’ to economic growth and could see exports to the remainder of the UK drop by 80%. To solidify the argument, the report cites academic research which estimates that trade between the US and Canada is 44% lower than it would be if there was no international border between them.

“International evidence shows that flows of trade, labour and capital are much larger between two regions of the same country than between two (otherwise similar) regions of two different countries”.

The conclusion therefore gravitates towards the potential damage to the macroeconomic environment because of the extent to which the Scottish economy relies on the remainder of the UK for its imports and exports.

Today, Labour Party politician Gordon Brown re-enters the independence debate with a keynote speech. A recent opinion poll showed that the pro-UK referendum campaign has opened up a 30-point lead over its opponents.